This invention relates to a data-indicating device, particularly but not exclusively to a perpetual calendar.
The invention provides a data-indicating device comprising a plurality of rotatable disc-shaped members carrying data selectively viewable through see-through portions of a cover, at least one of the disc-shaped members having an outer peripheral portion carrying data and an inner portion through which data on a further data carrier arranged behind the inner portion is selectively viewable.
As a result, a relatively-large data-displaying area in relation to the total surface area of the device is obtainable because of the see-through inner portion of at least one of the discs. This see-through portion may be provided by forming the inner portion of the disc of transparent material.
Preferably, the device comprises a first rotatable disc having a transparent inner portion and an outer peripheral portion carrying data and a second rotatable disc carrying data and arranged behind the first disc, the data on the second disc being selectively viewable through the transparent inner portion of the first disc.
It is the object of the present invention to obtain, in an indicator device of the above-mentioned type, an increase of the area for listing and reading of the numbers of the date-listings or similar data, without thereby necessitating an increase of the outer dimensions of the calendar or similar indicator device.
Thus, in comparatively small peripheral portions of the calendars, the area-section which is available for displaying the data, in comparison to the total area of the calender, can be made relatively large. It is now possible to make available area-portions which formerly could not be utilized for displaying the dates, on the basis of the above-explained transparency of the see-through portion. This produces the advantage that in comparatively small calendar-dimensions the dates to be displayed can be kept relatively large and therefore will enable a clearer reading of the dates from a greater distance.
It is thus possible that the first disc-shape member of a preferably larger diameter may be selected in such a size so that it obtains approximately the external diameter of the calendar or indicator device, or its cover plate, whereby the dates, which have to be displayed on that portion of the periphery of the disc, can be accordingly large. Additionally, it provides for a greater freedom in the selection of the diameter and the positioning of the further disc of the calendar or indicator device. For the disc which is proposed to be positioned behind the transparent portion of the first disc, it will suffice if the portion of the disc carrying the dates is located behind the transparent portion of the first disc, i.e., being in alignment with the corresponding see-through portion of the cover plate.
In the preferred area of application of the instant invention, namely, in a permanent calendar device, the outer closed or non-transparent cover portion of the first disc, having a larger diameter can serve for the units-digits of the months and the second disc of the smaller diameter can serve as the carrier for the tens-digits of the months, whereby the discs are measured to such an extent, and are arranged to the see-through portions of the cover plate so that the tens-digit numbers can be placed behind one see-through portion which is located at the left adjacent the see-through portion of the cover plate for the units-numbers. This will permit a large amount of numbers to be assigned to the larger disc, namely, the units-numbers, from 0-9, while in comparison thereto the smaller disc must be provided with only the numbers 1, 2 and 3, wherefore their circumference will suffice completely.